As computer and other digital systems become more complex and more capable, methods and hardware to enhance the transfer of data between system components or elements continually evolve. Data to be transferred include signals representing data, commands, or any other signals. Speed and efficiency of data transfer is particularly critical in systems that run very data-intensive applications, such as graphics applications. In typical systems, graphics processing capability is provided as a part of the central processing unit (CPU) capability, or provided by a separate special purpose processor such as a graphics processing unit (GPU) that communicates with the CPU and assists in processing graphics data for applications such as video games, etc. One or more GPUs may be included in a system. In conventional multi-GPU systems, a bridged host interface (for example a peripheral component interface express (PCIE)) interface must share bandwidth between peer to peer traffic and host traffic. Traffic consists primarily of memory data transfers but may often include commands. FIG. 1 is a block diagram of a prior art system 100 that includes a root 102. A typical root 102 is a computer chipset, including a central processing unit (CPU), a host bridge 104, and two endpoints EP0 106a and EP1 106b. Endpoints are bus endpoints and can be various peripheral components, for example special purpose processors such as graphics processing units (GPUs). The root 102 is coupled to the bridge 104 by one or more buses to communicate with peripheral components. Some peripheral component endpoints (such as GPUs) require a relatively large amount of bandwidth on the bus because of the large amount of data involved in their functions. It would be desirable to provide an architecture that reduced the number of components and yet provided efficient data transfer between components.